General security systems are installed in areas which lack security to report the occurrence of an emergency such as violence, an emergent state, etc. and respond thereto. Security systems include cameras installed in areas with vulnerable security and a camera controlling apparatus for controlling cameras. Each of cameras transmits images taken at an area with vulnerable security to the camera controlling apparatus in real time, and a user monitors each of images output on a display apparatus provided in the camera controlling apparatus and recognizes and determines whether an emergency occurs. Camera-based security systems have a problem that a time consumed for responding to the emergency varies according to abilities of users for recognizing the occurrence of an emergency. Accordingly, recently, there has been applied a technology in which a camera controlling apparatus of a camera-based security system performs image recognition processing on an image transmitted from each of cameras, detects each of objects in the received image, compares a relationship between detected objects with prestored situation data to automatically determine whether an emergency occurs. However, when predetermined situation data does not correspond to the relationship between the detected objects, the camera determines that an emergency does not occur. Also, since the camera controlling apparatus determines an emergency based on a signal of an image taken and transmitted by a camera, it is impossible to respond to an emergency which occurs in a dead zone for cameras.
Meanwhile, recently, measures for preventing school violence are social issues. Conventional camera-based security systems can not recognize an emergency such as school violence, an emergent state, etc. which occurs in a dead zone for cameras. However, a plurality of wireless emergency bells of a wireless emergency bell control system may be installed in areas with vulnerable security without constraints of space, thereby removing a blind spot of security. When an emergency occurs, a party to an accident or a person who recognizes the emergency may spread or report the occurrence of the emergency to others through an installed emergency bell. The wireless emergency bell control system, unlike security systems based only on cameras described above, may immediately determine whether an emergency occurs and may immediately respond to the emergency.